The present invention relates to a method and a device for converting cheap and "unlimitedly" available low temperature heat energy into useful mechanical work, which e.g. can be utilized for producing electric energy, and/or high temperature heat energy.
I have previously developed various types of heating systems, wherein low temperature heat energy is taken mainly from solar energy stored in ground accumulators, e.g. such accumulators as are described in my Swedish Pat. No. 400,631, which is incorporated herein by reference. In such systems heat pumps are used for converting the stored low temperature heat energy to high temperature heat energy for heating purposes. A further development of these heating systems, e.g. described in my German "Offenlegungsschrift" No. 28 43 349 (corresponding to my copending U.S. Pat. Ser. application No. 946,238), which is also incorporated herein by reference, makes it possible to simultaneously convert the low temperature energy into mechanical/electrical energy by utilizing the expansion work of the heat pumping device.